What is MPLS? A Step-by-Step Guide

OK, so you've already asked "what is MPLS?". The problem is that you got a techie-answer that was so full of jargon that you still don't know how this technology really works.

If you're looking for a direct, easy-to-understand answer to the "what is MPLS?" question, read on.

MPLS stands for "Multi-Protocol Label Switching". In order to understand exactly what that means, you have to break it down:

"Multi-Protocol" means that these networks are capable of handling all kinds of different data. Whether you need to send and receive emails, real-time video, or a voice stream, these networks can do it -- quickly. In fact, MPLS networks are some of the fastest technology in the world.

"Labels" refer to the way data is packaged when it travels along the network. Instead of just letting it flow freely, data is packed up into a neat little packet before it gets sent anywhere. On the front of each packet is a label that says where the packet came from and where it needs to go. It's kind of like the gift tags you see on presents -- complete with a "To" and a "From".

When a packet of data arrives at a "rest stop" along the network (called a "hop" in techie-speak), the network looks at the label to figure out where the data has to go next.

That's much more efficient than other forms of technology -- where your router has to dig into the packet, see what's inside, so that it can figure out where to send it. It would be like if you didn't put an address label on one of your gifts -- and, instead, forced the mailman to open the package up, see what was inside, and figure out who you were sending it to. It's definitely not an efficient way to do things!

"Switching" is the process of changing labels as the data travels. Once a packet of data arrives at its first hop, it has to get a new label. That way, the network knows which hop to send it to next.

Since all of the labels get changed from hop to hop, each packet of data can take its own unique path to its destination. For example, if you've got really important data (like a live video stream of your surveillance camera) that you can't afford to wait a few extra seconds for, you can set up your network so that those data packets get special labels. That way, your network will know to give those packets priority service -- meaning they'll take a more direct route.

Got it now? Great! Now you know exactly how MPLS works -- and, more importantly -- how it can help you!